#include<stdio.h>
void main()
{
	float a=1,b=2,c,e,sum=0;
	int i;

	for(i=1;i<=20;i++)
	{
		e=b/a;
		sum=e+sum;
		c=b;
		b=a+b;
		a=c;
	}
	printf("sum=%f\n",sum);
}
